RNAi-Based Gene Silencing of RXLR Effectors Protects Plants Against the Oomycete Pathogen Phytophthora capsici
RNAi-Based Gene Silencing of RXLR Effectors Protects Plants Against the Oomycete Pathogen Phytophthora capsici
复制标题
基于RNAi的RXLR效应子基因沉默保护植物抵抗卵菌病原体辣椒疫霉
DOI：
10.1094/mpmi-12-21-0295-r
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发表时间：
2022-04-26
影响因子：
3.5
通讯作者：
He, Shuilin
中科院分区：
文献类型：
--
作者：
Cheng, Wei;Lin, Menglan;He, Shuilin
辣椒疫霉是一种寄主范围广的卵菌病原菌，可引起辣椒等数百种植物的疫病。辣椒疫霉的自然抗性不足，现有的化学杀菌剂很难控制。因此，迫切需要开发控制该病原体的替代策略。近年来，寄主诱导或喷雾诱导的病原体基因沉默为病害控制提供了一种有效的策略。在这里，我们证明了辣椒疫霉可以有效地从环境中摄取小干扰RNA（siRNA）。根据RNA-seq和定量逆转录PCR分析，我们鉴定了4个在感染阶段显著上调的辣椒疫霉RXLR效应基因。瞬时过表达和启动子感染试验表明，RXLR 1和RXLR 4可以促进病原菌的感染。在辣椒植物中使用病毒诱导的基因沉默系统，我们发现在植物中表达靶向RXLR 1或RXLR 4的RNA干扰（RNAi）构建体可以显着减少病原体感染，而共干扰RXLR 1和RXLR 4可以赋予对辣椒疫霉的更增强的抗性。我们还发现，外源施用靶向RXLR 1或RXLR 4的siRNA可以抑制辣椒疫霉菌在辣椒和烟草叶片上的生长;当同时靶向RXLR 1和RXLR 4时，控制效果更加显著。这些数据表明，基于RNAi技术的RXLR效应子基因沉默在辣椒疫霉菌的作物改良中具有巨大的应用潜力，也为基于RNA的抗卵菌剂的开发提供了重要基础。
Phytophthora capsici is a broad-host range oomycete pathogen that can cause severe phytophthora blight disease of pepper and hundreds of other plant species worldwide. Natural resistance against P. capsici is inadequate, and it is very difficult to control by most of existing chemical fungicides. Therefore, it is urgent to develop alternative strategies to control this pathogen. Recently, host-induced or spray-induced gene silencing of essential or virulent pathogen genes provided an effective strategy for disease controls. Here, we demonstrate that P. capsici can effectively take up small interfering RNAs (siRNAs) from the environment. According to RNA-seq and quantitative reverse transcription PCR analysis, we identified four P. capsici RXLR effector genes that are significantly up-regulated during the infection stage. Transient overexpression and promote-infection assays indicated that RXLR1 and RXLR4 could promote pathogen infection. Using a virus-induced gene silencing system in pepper plants, we found that in planta-expressing RNA interference (RNAi) constructs that target RXLR1 or RXLR4 could significantly reduce pathogen infection, while co-interfering RXLR1 and RXLR4 could confer a more enhanced resistance to P. capsici. We also found that exogenously applying siRNAs that target RXLR1 or RXLR4 could restrict growth of P. capsici on the pepper and Nicotiana benthamiana leaves; when targeting RXLR1 and RXLR4 simultaneously, the control effect was more remarkable. These data suggested that RNAi-based gene silencing of RXLR effectors has great potential for application in crop improvement against P. capsici and also provides an important basis for the development of RNA-based antioomycete agents.